I live on the east coast in OZ, redbacks seem to like it down here in Victoria, but only ever seen them outside, they seem to like getting underneath things and if you disturb them ya gota move quick.

The biggest spider i have seen down here was one day when my nephew was washing his car on the front lawn, he stuck the hose in the back wheel arch and this spider come out this thing was a monster, much much bigger than a mans hand, like a crab , i never seen anyone move so fast i my life
i couldn't stop laughing, my poor nephew got a hell of a shock, he turned white and all, i grabbed a long shovel and chased it to try to kill it but it was to quick for me, but from that day onwards he only took his car to the car wash.
So yeah there around but don't bother us unless we happen to bother them.

Brian